Recently various sources of alternative energy have been developed for environment-friendly energy resources, and photovoltaic power generation is one of those which call attention. Photovoltaic power generation has an advantage in eliminating the fueling cost affecting the unit price of power generation. However, photovoltaic power generation requires the cost for construction site, installation, maintenance and repair, which also significantly affects the unit price of power generation.
Conventionally photovoltaic power generation has been achieved by arranging in a given range the solar panels for collecting light rays to generate power. Specifically, the solar panels have been arranged in a single layer over a wide area. They are used in a large scale in a desert and a salt farm region, or in a small scale on the roof of a building.
Such a conventional method suffers a limitation in collecting light rays owing to the planar type solar panels. For example, Korean Laid-Open Patent Publication No. 2011-0087134 (Laid-Open Number) discloses a planar type solar panel. Moreover, the single layer arrangement of the conventional method suffers a disadvantage in paying a high cost to obtain a site for constructing a photovoltaic power generation facility.